Some 300 migrants began to march yesterday from Belgrade towards Hungary in a bid to enter the European Union, two days after a void referendum in Serbia’s northern neighbour.Escorted by police from Belgrade to Zemun, a northwestern suburb of the capital, they began their 200km trek towards the Balkan nation’s northern border.They earlier held a brief protest in downtown Belgrade against EU member Hungary’s bid to keep all migrants and refugees out.“We don’t need water and food, we urge you to open the borders,” read one of the banners carried by the protesters.Several protesters contacted by an AFP photographer said that they were from Afghanistan.A similar attempt to break through the border in July ended in failure.Low voter turnout voided a referendum on Sunday that President Viktor Orban hoped would enable Hungary to reject a EU migrant quota plan.The number of migrants blocked inside Serbia has grown significantly since Hungary introduced tough new measures in July aimed at stopping them crossing the border.According to the UN refugee agency, more than 5,500 migrants are currently stuck in Serbia, which estimates it can accommodate 6,000 to 7,000 people.Serbian President Tomislav Nikolic on Monday voiced concerns over the situation and said it might have to “close the border to migrants” if they continued to enter the country without being able to continue their onward journey to western Europe.Serbia lies on the so-called Balkan route taken by hundreds of thousands of migrants from the Middle East, Asia and Africa since mid-2015 on their way to western Europe.Although the route was effectively shut down in March, migrants have continued to cross the region in smaller numbers – a few hundred a day – often with the help of traffickers.According to Serbian authorities, more than 102,000 migrants have been registered in the country since the beginning of the year.